This invention relates to a substrate conveying system and a substrate conveying method with a substrate temperature adjusting function, being usable in a semiconductor device manufacturing system, for example, for conveying a substrate such as a wafer onto an exposure stage, for example. In another aspect, the invention concerns a semiconductor manufacturing apparatus or a device manufacturing method using such a substrate conveying system.
In a semiconductor manufacturing system, different semiconductor manufacturing apparatuses are used to perform plural processes to a wafer to thereby produce semiconductor devices. In these semiconductor manufacturing apparatuses, temperatures suitable to the processes are different and, therefore, it is necessary to control the wafer temperature in each semiconductor manufacturing apparatus.
Particularly, in a semiconductor exposure apparatus, if the wafer temperature differs from the inside temperature of the semiconductor exposure apparatus, thermal distortion will be produced in the wafer. On that occasion, even if a projection optical system having a good resolving power is used, a desired linewidth exposure is not attainable. The registration precision cannot, therefore, be high. Thus, the wafer temperature control is necessary.
Conventionally, temperature adjusting means for wafer conveyance comprises an intermediate transfer table inside a conveyance system unit, which table is equipped with a temperature adjusting mechanism. As a substrate is loaded on the intermediate transfer table by the conveying system, the wafer temperature adjustment is carried out. Then, the temperature-controlled wafer is conveyed
However, in such temperature adjusting means wherein an intermediated transfer table (temperature adjusting unit) having a substrate temperature adjusting mechanism is used so that a wafer is once conveyed to the temperature adjusting unit and then the substrate temperature is adjusted, it takes an additional time to transfer a substrate to the temperature adjusting unit. The overall processing speed in the semiconductor manufacturing apparatus is thus lowered, by an amount corresponding to the time required for the substrate temperature adjustment by the temperature adjusting unit. Further, the addition of substrate transfer operations causes adhesion of contaminants. Moreover, the provisions of such a substrate temperature adjusting unit results in bulkiness of the conveying system itself.
Further, since, in such a temperature adjusting unit, the heat exchange is carried out by contact to substantially the whole bottom surface (lower face) of the wafer, the transfer operation of the wafer to a hand mechanism of the conveying system needs to push the wafer upwardly through three pins. This pushing operation further lowers the overall processing speed of the semiconductor manufacturing apparatus. Also, there is an inconvenience of production of dust particles.
It is accordingly an object of the present invention to provide a substrate conveying system and/or a substrate conveying method by which a temperature of a substrate can be adjusted without a decrease in an overall processing speed of a semiconductor manufacturing apparatus and without enlargement of the contamination production frequency.
In accordance with an aspect of the present invention, there is provided a substrate conveying system, comprising: a transfer station whereat a substrate can be transferred between said substrate conveying system and a particular system different from said substrate conveying system, said transfer station having a substrate temperature adjusting plate for adjusting a temperature of the substrate; and substrate conveying means for conveying between said transfer station and a desired position.
The substrate temperature adjusting plate may have at least three protrusions formed on its surface, for supporting the substrate.
Heat exchange may be carried out through a clearance defined between the substrate and said substrate temperature adjusting plate.
The clearance defined between the substrate and said substrate temperature adjusting plate may be not greater than 0.2 mm.
The substrate temperature adjusting plate may have a notch defined so that said plate does not interfere with a substrate holding portion of said substrate conveying means when the substrate is to be transferred.
In accordance with another aspect of the present invention, there is provided a substrate conveying method, comprising the steps of: conveying a substrate from a particular system to a transfer station whereat a substrate can be transferred from or to the particular system; adjusting a temperature of the substrate at the transfer station; and conveying the substrate from the transfer station to a desired position.
In accordance with a further aspect of the present invention, there is provided a semiconductor manufacturing apparatus including a substrate conveying system as recited above.
In accordance with a yet further aspect of the present invention, there is provided a device manufacturing method including a process for manufacturing a semiconductor device by use of a semiconductor manufacturing apparatus as recited above.